Shop for mp3 players

Digitizing Music

At their most basic level, digital music formats such as MP3s looks a lot like any other computer data file: a long series of 1s and 0s. In order to turn an analog signal (such as one picked up by a standard microphone) into a digital stream, ADC (analog-to-digital converter) software measures the signal at a regular interval to find the sampling rate. These samples, if measured close enough together, form a near-exact representation of the analog signal so as to approximate the transmission using 1s and 0s that computers and MP3 players can read.

Compression

Each second of true CD-quality sound takes up more than 1.3MB of disk space, which is why file-compression technology is essential to digital audio, especially portable audio. Using principles of psychoacoustics (how the brain perceives sound) and perceptual coding (eliminating imperceptible sounds), engineers develop algorithms, called codecs (compression decompression), that compress songs into the smallest possible sizes with minimal loss of quality. The sound depends on two factors: the quality of this compression algorithm and the bit rate at which the song is encoded, measured in Kbps.

Playback

When you play a digital file, you essentially reverse the analog-to-digital process. A digital audio device, such as an MP3 player or a computer sound card, uses a DAC (digital-to-analog converter) to turn the 1s and 0s back into an analog signal that can then be amplified and broadcast over headphones or speakers. The sound depends on the attributes and quality of the digital file, the DAC chip in the player, the amount of distortion and hiss added by interference from the device's other circuitry, and the audio output level of your headphones or speakers.

When a digital device plays music that has been compressed by a codec, software on its chip (called firmware) applies the codec to decode the file, then sends the decompressed 1s and 0s to the DAC.

File formats at a glance

The first format or codec to gain widespread acceptance was MP3, but there are now a variety of players on the market that support AAC, WMA, OGG, and other formats. This table will help you sort out the alphabet soup and determine which codecs you need in an MP3 player.

These days, manufacturers are adding an ever-widening array of features to their players in order to set them apart from the competition. These are the extras that you may want to consider.

Color screens, photo viewing, and video playback

Most MP3 players now come equipped with a color screen that can display JPEG and BMP digital images. This is a nice feature for those who like to carry their precious digital memories with them. In addition to offering photo viewing capabilities, color displays are brighter and easy to read than their monochrome counterparts. Also look out for players with crystal-clear OLED screens, which offer better viewing angles and lower power consumption (though they are harder to read in bright sunlight). Increasingly, MP3 players are even offering video playback. Although the screen on a typical MP3 player is too small for extended video viewing (for that, try a PVP instead), it can be a nice bonus for certain users, such as commuters.

Radio

Many players offer FM radio reception, although they're more common on flash devices, which lack the spinning hard drives and the CD-playing features that can interfere with the signal. AM radio is extremely rare. Other radio-related features include FM recording (usually to MP3), transmission (for playing back audio wirelessly through home and car stereos with FM tuners), and presets.

Wireless capability

The latest technology to be cropping up in MP3 players is wireless connectivity. A prime example is the Microsoft Zune, which uses proprietary Wi-Fi to allow users to share songs with each other over the airwaves via a beaming feature. There's also the SanDisk Sansa Connect, which can hop onto any Wi-Fi network to access the Yahoo Music store for wireless music purchasing and downloads. Yet another--and very different--example is the Insignia MP3 Player & Image Viewer. This player offers built-in A2DP Bluetooth, meaning it can be paired with a compatible pair of wireless headphones for a cord-free listening experience. Wireless functionality is still in the up-and-coming stages, so the execution may not be perfect on many devices quite yet. Still, if you're looking for the cutting-edge, this is it. For more information, check out this feature.

Music Recording

Most MP3 players that record high-quality audio suitable for music recording as opposed to voice memos or interviews do so through an analog line-input, but there are exceptions. A few devices also record digitally or from mike-level sources. The former works great for dubbing tracks from modern stereo components. The latter lets you use a small, unpowered microphone for live recording. (You can record live audio without a mike-level input but only with a powered mike that outputs a line-level signal to the device's line-in jack.) If you want the highest-quality recordings, make sure the player has a decent ADC and can record to uncompressed WAV files. Real-time encoding to MP3 or WMA comes in particularly handy when encoding from vinyl, cassette, or CD without a computer.

Voice recording

Some MP3 players have a small internal microphone for recording the spoken word. These are acceptable for documenting a lecture, a meeting, or a conversation but unsuitable for high-quality music recording. The sampling rate is typically low, and the recordings are mono. The upside is that you can usually record several hours of memos, then upload the files to your PC for attaching to e-mail or archiving.

Data storage

Many MP3 players can double as external storage devices, allowing you to shuttle data between PCs. Some models don't even require drivers; thus, you could transfer a resume or a presentation to the laptop of the person seated next to you on a flight. So-called plug-in players don't even need a cable since they have built-in USB connectors.

Personal information management

Some MP3 players--notably the Apple iPod and Creative's Zen line--can accept phone books and schedules. The information is generally entered into Outlook or another PIM program, then synced to the device where you can view it but not change it on the go. These features tend to be limited and, for most, won't replace a handheld.

Sound-tweaking options

Audio purists generally prefer to hear songs exactly the way the recording engineers mixed them and don't have much use for digital signal processing (DSP), which changes a song's equalization or spatial characteristics. But since digital audio files come from multiple sources and people have individual sonic preferences, EQ and other DSP settings can be useful. Look for a customizable EQ setting (the more bands the better; five is the norm), as well as the standard presets (Rock, Jazz, Bass Boost, and so on). In terms of spatial enhancers, DSP features such as the SRS Wow add-on can make music coming through headphones sound like it's bouncing around a large room. It's purely a matter of personal preference, but we think music sounds better with some degree of customization.

Advanced playback features

Just about every player offers shuffle, repeat, resume, and playlist functions. Still, there's room for improvement. Newer models offer the ability to create on-the-fly playlists sans a computer; smart playlists that can serve up, for example, a mix of '80s hip-hop; song-rating methods in which preferred tunes appear more frequently in Shuffle mode; automatic cross-fading that adds smooth transitions between songs; automatic volume control, which makes all songs equally loud; and other artificial intelligence modes that can make it feel like a pro DJ is spinning tunes for you.

Battery type and life

Our Personal Tech Radar survey found that our users view battery life as a critical factor. Most hard-drive-based players come with nonremovable lithium ion batteries, which typically last two to four years. Many manufacturers have some sort of return/repair plan, so check the warranty policy before you buy (the typical replacement cost is about $100).

Flash and MP3 CD players are split between those using AA or AAA batteries and those with an internal rechargeable cell. Since flash players need to be synced more often and it's easy to recharge as you sync, flash players with rechargeable batteries are usually preferable. Generally speaking, the larger the player, the longer the battery life, but this isn't always the case, so be sure to read the battery-test results in our reviews before you pull out your wallet.

MP3 players are definitely not one-size-fits-all. They come in a range of shapes and sizes, use different types of memory, and support different formats. Based on these and other features, certain players are better suited to certain uses--you should choose the player (or players) that meets your needs. Check out the various uses for an MP3 player and figure out which players are up to the task.

As we see it, here are some top uses for MP3 players, as well as some questions that you should consider in order to figure out if one or more of these usage models will suit you. Some people align with more than one use, and they should possibly consider buying more than one MP3 player to address various needs. For instance, you might want an ultracompact flash player for jogging or skiing and a high-capacity hard-drive-based device for traveling.

Of course, plenty of people just want an MP3 player for general, day-to-day use. If you're simply after a device that plays good-sounding music and is easy to use, any of the top products listed are perfectly suited for this. However, if you're looking for a device for a particular use, read on.

Commuting

Working out

Traveling

Listening to audiobooks

File hoarding

Recording audio

Watching video

Back when the cassette Walkman ruled the portable audio domain, you didn't have to seriously think about whether your player would play the music you bought. And when the first widespread digital format (the compact disc) was introduced, consumers faced relatively minor compatibility issues; you had to buy a CD player but could record cassette mixes from CDs without a lot of hassle. With an MP3 player, you have to consider where your music is coming from to ensure your device will play your music. Here's what you need to know about music compatibility.

Existing music on your computer

If you've already ripped and/or downloaded lots of music, choose a player that supports the format(s) you're already storing. If it's MP3, you're OK with any player, but rarer formats are supported by only certain devices. When you're reading one of our MP3 player reviews, check out the Features or Specs tab to find out which formats the device takes.

Compact discs

If all of your music is still on CDs, you can buy just about any MP3 player since you'll first need to convert your discs to MP3, WMA, OGG, or one of the other formats mentioned earlier. Normally, the necessary software is included with the player, but if not, try MediaMonkey. You'll typically use that software to organize the music files, set up various playlists, and transfer music to your device.

Online music stores

Online music stores were once a tangled mess of competing audio formats and copy protection restrictions. Fortunately, the success of online retailers such as eMusic and Amazon has sparked a growing trend toward universally compatible music downloads in the MP3 format. One major exception to the trend toward unrestricted MP3 sales is Apple's successful iTunes music store, which sells a mix of protected and unprotected AAC music files.

One important note: Digital audio devices sometimes support the unprotected version of a certain codec but not the secure version. For instance, some MP3 players play normal, unprotected WMAs that you create from your own CDs but not the secure WMAs sold by online music stores such as Napster, Rhapsody, Yahoo Music, and so on. On the plus side, the music industry is starting to show an inclination to sell more unprotected formats online. For example, EMI has already agreed to sell DRM-free AAC files through iTunes. These files can then be played on, say, the Microsoft Zune, which supports AAC files, but only if they are unencumbered by DRM.

The files sold by these stores come with usage restrictions that commonly limit playback to three computers and stop you from mass-producing burned mixes. These restrictions can cause device compatibility problems, but the trade-off for consumers is that those safeguards make the labels comfortable enough to license their songs to online stores.

Subscription-based music services

Imagine legally filling up your MP3 player with endless gigabytes of tunes from an online music store and paying less than the price of a CD. How is this possible? Well, you're not actually buying the tracks; instead, you're renting them in an all-you-can-eat scenario for a monthly subscription fee. Sounds attractive, no? Welcome to the fresh new world of the on-the-go music subscription service. For more information, check out our guide to on-the-go music subscription services.

P2P networks

Most tunes available on file-sharing networks (also called peer-to-peer or P2P networks) are already in the MP3 format, so there are no compatibility issues in this situation. Since someone else did the encoding, however, the audio quality of files on these services varies. Also, the legality of these sites is seriously questionable, so there's a risk of getting in trouble with the RIAA, which could lead to hefty fines or even jail time.

Vinyl/cassettes

If you have lots of music on vinyl, cassettes, or even 8-tracks, you can record it on to your computer, turn the files into MP3s, then transfer those to any MP3 player. In order to simplify the process, consider buying a player that has line-in recording and allows you to encode MP3s directly from your stereo. If your stereo has a digital optical output and you want to record MP3s this way, make sure to find a player that has a digital optical input; this will preserve sound quality during the recording process. If there's no digital optical output on your stereo, any player with an analog input will do. If you end up with a player that lacks line-in recording, visit our Weekend Project for digitizing LPs and cassettes.

By now, you should have a pretty good idea of how to choose an MP3 player. But the fun isn't over yet. You can pick from an endless number of accessories that will enable you to use an MP3 player as your car stereo, protect your hardware, improve your player's sound quality, and much, much more. Here are the main types of add-ons for portable audio players.

Headphones

Some people don't care about which headphones they use, but they probably haven't tried on a high-end pair; the difference will blow you away. The sound quality on MP3 players varies but nowhere near as much as that of headphones, so be sure to budget for a new set. If you want more "oomph" from your digital music, bite the bullet and invest in a decent pair--your ears will appreciate it.

Optional add-ons

Scour product reviews and manufacturer Web sites to determine whether any optional add-ons are available. Examples include in-line remote controls, jogging kits, deluxe carrying cases, flash memory adapters, FM transmitters, flash memory, docking stations, USB/FireWire kits, extra rechargeable batteries, car adapters, and more. Just because these extras are optional doesn't mean they won't enhance your enjoyment of the device.

How about using an MP3 player in your car? As far as cassette adapters go, they work with anything that has a mini headphone jack, so there are no compatibility issues. Yet you have to be really careful with power adapters for both car cigarette lighters and wall plugs. Use only those provided by the manufacturer; even if the plug physically fits, you still need to confirm the adapter's polarity, voltage, and amperage. While amperage can usually be 20 percent less or up to 100 percent more than what's needed by the player, polarity and voltage must be identical to the unit's requirements. If you're unsure about these factors, skip the bargains and buy the power adapter sold by the manufacturer--you'll avoid frying your player.